The hypothesis of this study was that different plant hosts of the medfly Ceratitis capitata may cause variability as a prerequisite for its invasiveness. The main objective was to determine population variability based on medfly wing shape in three favorable medfly host plants (peach, fig and mandarin) from different agroecological growing areas with different pest management practices, and to evaluate phenotypic plasticity as a basis for future expansion into new areas and new hosts. Using geometric morphometric methods across 14 specific landmarks on the medfly wings, 10 populations were tested from infested peach, fig and mandarin fruits, as well as laboratory-grown sterile populations. The studies led to the following main findings: (1) all of the medfly populations that were studied exhibited sexual dimorphism in wing shape; (2) the hosts in which the medfly develops influence wing shape and condition its variability; (3) there is significant variability between laboratory mass-reared sterile and wild individuals in male and female populations; (4) a high phenotypic plasticity of medfly populations was observed along the study sites. Even the low but clearly detected variability between different agroecological conditions and localized variability indicate genotypic stability and high phenotypic plasticity, which can be considered as a prerequisite for medfly invasiveness and dispersal to new areas.

Citrus fruits, particularly mandarins, are highly valued globally for their nutritional benefits and versatile culinary uses. However, the challenge of post-harvest decay, primarily due to blue mold (Penicillium italicum) infections, results in significant food losses and necessitates effective preservation strategies. Traditional methods often rely on fungicides, raising concerns about chemical residues and environmental impact. This study investigates the efficacy of ozone as an alternative approach to controlling blue mold in mandarins. Various gaseous ozone treatments were tested, including single, double, and triple treatments, with durations ranging from 10 to 60 min and concentrations from 3.3 to 20 ppm. Additionally, ozonated water treatments were evaluated with concentrations of 2, 4, and 6 ppm. To simulate a realistic infestation scenario, mandarins were artificially infected with P. italicum spores before undergoing both gaseous ozone and ozonated water treatments. The storage conditions for the mandarins were meticulously controlled, maintaining a humidity level of 50–60% and a temperature range of 10–12 °C. Each fruit was analyzed, and the presence of P. italicum infection was determined two and three weeks after the ozonation. Results indicated that ozone treatments significantly reduced mold growth, with gaseous ozone demonstrating efficacy rates up to 97.5% and ozonated water treatments achieving preservation rates between 95% and 97%. These results underscore ozone’s potential as a safe, efficient, and sustainable alternative to conventional fungicides, offering promising solutions for extending the shelf life of mandarins. Further research is recommended to optimize ozone treatment parameters, assess long-term effects on fruit quality and nutritional content, and refine application techniques to harness ozone’s potential in citrus fruit preservation fully. This approach not only addresses food security challenges but also aligns with global efforts to reduce chemical inputs in agriculture and promote environmentally sustainable practices.

The box tree moth (Cydalima perspectalis Walker, 1859; Lepidoptera: Crambidae) is an invasive species naturally distributed in Asia. The caterpillars in all developmental stages cause damage through defoliation of plants, and ultimately the death of the plant itself may occur. It is possible to recognize this species by its silk barriers and threads, and in the case of an intense attack, the entire plant will be covered with them. In Europe, this species’ presence was first recorded in 2007 in Germany and the Netherlands, and it is now widely distributed. In Croatia, its existence was first recorded in 2012, in Istria, while substantial damages were recorded in 2013. This work aimed to determine the morphological variability of C. perspectalis from Croatia and assess its invasive character, the possibility of flight, and the risk of further spread. The methods of geometric morphometrics were used as the analysis of wing shape. A total of 269 moths from different locations in Croatia were collected, the upper wings of males and females were analyzed using 14 landmarks. Significant differences in wing shapes between terrestrial and coastal populations were found, as well as subtle wing shape sexual dimorphism. The implications of this variability in species invasiveness and capacity of spread are discussed in this paper. We also extrapolate the usefulness of our results and suggest strategies for predicting and managing invasive species.

A prototype of an improved automated ground release machine was assessed and found, with further improvements, to have the potential to be a promising tool for the release of quality sterile Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) flies in small- and medium-scale SIT control programmes. The following quality parameters of sterile flies were assessed: (i) flight ability, (ii) physical damage caused by the ground release machine, (iii) survival under stress conditions without food and water and (iv) water condensation on flies, after 0.5 and 2 h under the automatically controlled abiotic conditions of 16 ± 0.8°C and ∼58% relative humidity. A total number of seven different treatments, five involving flies held inside the ground release machine and two control treatments of chilled and non-chilled flies not held inside the ground release machine, were evaluated to assess sterile male quality. Flight ability was as high as 97% in the control treatment (no ground release), compared with the lowest value of 92.5% when a 1-m-long screw-auger, as part of the ground release machine, was tested. Use of a 1-m-long screw-auger significantly increased the percentage of damaged flies up to 7.2%, compared with ≤1.7% in the control treatments. It is confirmed that the length of the screw-auger is the most important factor affecting quality of the released flies in the ground release system tested. Also, interaction of duration of time inside the machine, screw-auger rotation and the effect of the directional discharge blower significantly increases the percentage of damaged flies. Evaluation of sterile fly survival under stress conditions, without food and water, confirms that movement or handling of the flies inside the ground release machine drastically decreases percentage of live insects from ≤ 4.5% after 24 h and 0.0% after 48 h, compared with 18.67–21.67% after 24 h and 3.50–5.83% after 48 h in the control treatments. The most important factors affecting sterile fly quality, such as condensation, compaction and damage, from moving mechanical parts are demonstrated to be minimized or eliminated by making adaptations to the ground release machine construction.

The Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann 1824; Diptera, Tephritidae), is considered one of the most important pests, infesting more than 300 species of fresh fruit and vegetables worldwide. The medfly is an important invasive species, which has spread from the eastern part of sub-Saharan Africa to all of the world’s continents in recent centuries. Currently, the medfly is expanding its geographical range to cooler, temperate areas of the world, including northern areas of Mediterranean countries and continental areas of Central Europe. We collected and analysed all the available information, including in historical records, on the phenology of the medfly in the Balkan Peninsula, to map and understand the path of invasion and spread dynamics on the northern Mediterranean coast and in Central Europe. The medfly was first recorded in the Balkan Peninsula in 1915, in the Aegean area on the island of Aigina, followed by a few records on its presence in the Peloponnese in the early 1930s and throughout the Adriatic coastal area in the 1950s; it was first detected on the Croatian coast in 1947. By 2010, the medfly had been detected along the entire Ionian coast, while the first record of its presence on the Balkan coast of the Black Sea was made in 2005. Since 2000 to date, there has been a significant increase in the frequency of medfly detections in the interior of the Balkan Peninsula, including occasional detections in areas with unfavourable climatic conditions for overwintering, which seems to be favourable for reproduction during the summer and lead to significant infestation of late ripening fruits (late summer and autumn). In the last 20 years, the medfly has spread to more northerly areas (43 to 45 degrees latitude) and has been detected at higher altitudes (>200 to 600 m). Along the Balkan Peninsula, the infestation of fruits from 25 host plant species, from 14 genera and 10 plant families, has been reported. Considering the extremely high invasiveness of the medfly and its wide distribution in several Balkan regions with different climatic conditions, we can assume that it is adapting to new climatic conditions and infesting new host plants.